Improve `fluentd-async-connect` option
Improve `fluentd-async-connect` option

- According to https://github.com/moby/moby/blob/c093c1e08b605a6e4c763962c52e3c82ec0e934f/daemon/logger/fluentd/fluentd.go#L114 I added the _Defaults to `false`._ statement to `fluentd-async-connect` option.
- Add inline code formatting for other default values
thaJeztah/docker.github.io,docker/docker.github.io,docker/docker.github.io,londoncalling/docker.github.io,thaJeztah/docker.github.io,docker/docker.github.io,thaJeztah/docker.github.io,docker/docker.github.io,thaJeztah/docker.github.io,londoncalling/docker.github.io,londoncalling/docker.github.io,docker/docker.github.io,thaJeztah/docker.github.io,londoncalling/docker.github.io,londoncalling/docker.github.io